Guide for the weft thread inserting means in a loom for weaving and method of makingsame



1963 E. PFARRWALLER 3,

GUIDE FOR THE WEFT THREAD INSERTING MEANS IN A LOOM FOR WEAVING AND METHOD OF MAKING SAME Filed June 11. 1959 INVENTOR. few/1v Enema/41.452

Arm/max Bfildfibh Fatented Jan. 29, 1953 Edy/5,560 FUR THE WEEK 'ilrillEAl) HNSERTBNG MEANS lid A LGQM Fill? WEAVENG AND METH- Gl) i MAKlbiG SAME Erwin Piarrwailer, Winterthur, Switzerland, assignor to ulzer lFreres, 8A., Winterthur, Switzerland, 3 corporation 0r Switzerland Filed ll, 195?, Ser. No. 819,654 Claims priority, application Switzerland lune 28, 1958 2 Qlairns. (Cl. fil -4:88)

The present invention relates to a guide for guiding a weft thread inserting device in a loom r'or weaving while the inserting device travels through a shed formed by warp threads and more partciularly to guide elements forming part of the guide and being mounted like teeth of a comb on a carrier which is movable outside of the shed. The guide elements have a guide portion includ ing arms embracing the weft inserting device and entering and leaving the shed at each movement of the guide. The guide portion may also be described as having the general configuration of a beak whose jaws are open and adapted to receive the weft inserting device therebetween. Each guide element has a relatively Wide foot portion which is adjacent to the foot portions of the juxtaposed guide elements.

A particular object of the invention is the provision of a guide element of the type described above and being made in one piece by compressing a nonmetallic substance in one pressing operation to the final shape of the element.

The invention also relates to a method for making the aforedescribed guide elements by a pressing operation from nonmetallic substances, for example synthetic plastic material, such as nylon or sinter ceramic material. lt is advisable to subsequently impregnate the pressed elements, after they have been cooled, with a substance increasing slidableness, for example with a mixture containing oil. This facilitates sliding of the weft inserting devices through the guide elements and prevents absorption of moisture and deformation of the elements.

The novel features which are considered characteristic of the invention are set forth with particularity the appended claims. The invention itself, however, and additional objects and advantages thereof will best be understood from the following description of embodients thereof when read in connection with the accomanying drawing, in which:

FIG. 1 is a side view of a guide element according to the invention mounted on a lay which is partly shown in section. The figure also diagrammatically shows the guide element in the position outside of the shed and when entering the shed.

FIG. 2 is a side view of scale.

FIG. 3 is a sectional View of the guide part of the guide element, the section being made along line lll lll in FIG. 2.

P16. 4 is a top view of the element.

5 is a front view of the lower jaw of the guide element shown in FIG. 2.

F16. 6 is a front view of the foot portion of the guide element shown in FIG. 2.

Referring more particularly to the drawing, numeral it designates a guide element, mounted on a lay ll forward of a reed 12. The guide element has a guide portion 13 embracing a weft thread inserting element 14, for example a shuttle of a gripper shuttle weaving machine, when moving in a direction normal to the picking path of the shuttl The guide portion 1.3 is provided with an opening 15 affording lateral passage of a weft thread 16. llurnerals J7 and lit designate warp threads he guide element in larger top portion of the guide 23 forming a shed having an apex 19 where the finished fabric 21 begins. The latter is supported by a bar 22.

The guide elements it) are juxtaposed and have foot portions 23 which are adjacent or slightly spaced. Upon movement or" the lay 11 with the reed if; in the direction of the arrow 2 for beating up a weft thread 16, the guide elements ill leave the shed and move below the warp threads 1% to the position 1, shown in dash-dot lines in FIG. 1, below the fabric support 22.

Upon return of the lay ill to the rest position the elements ll) re-enter the shed 17, 13 between and separate the warp threads and come to rest in the position lV shown in solid lines in FIG. 1. The top 25 of the guide portion 1.3 is provided with an edge, as shown in FIG. 3, above a jaw portion 26 having a thickness :5 which is greater than the thickness d of the rest of the guide portion 13 as well as of a web portion 27 of the element 1%. The end of the lower part or prong 23 of the guide portion 1 is tapered or pointed as seen at 2i in FF". 5.

The thickened upper jaw portion 26 is the first part of the guide portion 13 which enters the shed when the guide element moves from position ii to position llI shown in FIG. 1. The thickened upper jaw portion 26 prevents crossing of juxtaposed warp threads l8 and moves these threads so far apart that the pointed end 29 of the lower prong or jaw 23 of the guide portion 13 can freely enter the shed between spaced warp threads 18 when the guide element reaches the position Ill. The conventional shuttle guide teeth, which are sheet metal stampings, permit crossed warp threads to enter through the opening 15 between the upper jaws 26 and the lower jaws Z3 and to be engaged by a shuttle. This is avoided by the guide element according to the invention. FIG. 4 shows the length of the thickened upper jaw portion 26.

The foot 2? of the element Elli is provided with lateral surfaces 4-1 which are parallel to the lateral surfaces of the web portion 2'7 and which are interrupted by two opposed grooves 31 having a semi-circular cross section. The grooves 31 of two juxtaposed guide elements are adapted to receive a stud 32 which extends through bores in a steel band 3:: into the lay ll. The foot portion of the guide element is provided with two surface portions 34, 35 for exact fitting on the lay 11 so that shuttle running surfaces 36 to 39 provided on each guide element are in accurate alignment. The foot portion 23 has recesses 42 so that the thickness of all parts is approximately equal to the thickness of the web portion "1'. In other words, the foot portion 23 includes rib ortions 24 extending laterally beyond the planes in hich substantially plane and parallel lateral suraccs of the web portion 27 are located. The thickness of these rib portions is substantially the same as that of the web portion 27 which is substantially as thick as the guide portion 1%. In this way not only the weight of the guide elements is reduced but also manufacture of he elements by pressing is facilitated.

The elements i made of nonmetallic material and are formed by pressing. Suitable materials are synthetic plastics and sinter ceramics. Preferably, pliant synthetic plastics, particularly nylon are used.

Due to the use of pressable nonmetallic materials, the guide elements can be made not only in one piece but also in one operation.

The conventional manufacture of guide elements by sheet metal stamping makes it necessary to provide spacers or to cast foot portions onto the elements for mounting the guide elements in the correctly spaced position on the carrier. Comblike spacers permit lateral clearances so that the guide elements are slightly inclined in the picking direction. Casting of foot portions on stamped sheet metal guide elements may cause warping g o as scrapes of the guide elements or teeth. In both cases the run of the shuttles is inaccurate and the guide elements are subject to excessive wear.

These disadvantages are avoided with the elements according to the invention in which the guide portion is relatively thin and the foot portion is relatively thick and both portions are made of one piece and in one operation. The fitting surfaces are plane and an increased taper is provided on the opposite surfaces to facilitate removal of the elements from the mold.

Manufacture of the guide element by pressing facilitates the provision or" a thickened upper jaw portion 25 at the top of the guide element for obtaining the desired parting of the warp threads. The reduction of the weight of the guide elements due to the use of nonmetal lic materials considerably reduces the mass to be moved for beating up the weft threads.

The use or; pliant synthetic plastics, particularly nylon, permits bending the top ortion or upper jaw 26 by hand into the ori inal position without danger of breakage, should this portion have been bent out of its correct position. If the proposed materials are used, a bent portion automatically returns to its original position within a short period of time.

It is of advantage to impregnate the guide elements, preferably with a mixture containing oil, This improves the glide properties and prevents moisture absorption of the guide elements so that swelling is avoided. Pressing is usually done at a temperature of about 425 F. so that any moisture in the material evaporates and the pores left in the pressed elements are ready to absorb the impregnating emulsion after the elements have cooled off. By impregnating the material, after it has been cooled, the pores are filled and the usually damp atmosphere in the weaving mill cannot cause undesired swelling of the otherwise very hygroscopic materials of which the new guide elements are made.

The use of synthetic plastics for making the guide elements has the further advantage that this material is more closely relat d to the material of the warp and weft threads than steel, of which the conventional guide elements are made. The desired result or" this relationship is reduction of pollution of the thread material and of the fabric and lessening of the danger of thread break" ages.

I claim:

1. A guide for guiding a weft thread inserting device in a loom for weaving while the inserting device travels through a shed formed by warp threads, the guide including a carrier, movable outside of the shed, and a plurality of like, juxtaposed guide elements, each guide element having a relatively thin beaklilze guide portion including an upper and a lower jaw, said jaws having converging ends and being adapted to receive the weft thread inserting device therebetween and entering and leaving the shed between warp threads during each movement of the guide, each of said guide elements having a relatively thicl; ioot portion which is adjacent to the foot p rtions of the juxtaposed guide elements, the lower jaw forming a running surface conforming substantially to the cross-sectional configuration of the lower part of the weft thread inserting device running on said running surface, said upper jaw of each guide element being thicker than said lower jaw for parting the warp threads when said guide portion enters and leaves the shed.

2. A guide for guiding a weft thread inserting device in a loom for weaving while the inserting device travels through a shed formed by warp threads, the guide including a carrier, movable outside of the shed, and a plurality of like, juxtaposed guide elements, each guide element having a relatively thin bcaklike guide portion including an upper and a lower jaw, said jaws having converging ends and being adapted to receive the weft thread inserting device therebetween and entering and leaving the shed between warp threads during each movement of the guide, each or" said guide elements having a relatively thick foot portion which is adjacent to the foot portions of the juxtaposed guide elements, the lower jaw forming a running surface conforming substantially to the cross-sectional configuration of the lower part of the weft thread inserting device running on said running surface, each of said guide elements including a substantially plane web portion interposed between said guide portion and said foot portion and having two substantially plane and parallel lateral surfaces, said web portion having substantially the same thickness as said guide portion, said foot portion including rib portions projecting laterally from each of the planes of said parallel surfaces to an extent substantially equal to the thickness of said web portion.

References Cited in the file of this patent UNlTED STATES PATENTS 

1. A GUIDE FOR GUIDING A WEFT THREAD INSERTING DEVICE IN A LOOM FOR WEAVING WHILE THE INSERTING DEVICE TRAVELS THROUGH A SHED FORMED BY WARP THREADS, THE GUIDE INCLUDING A CARRIER, MOVABLE OUTSIDE OF THE SHED, AND A PLURALITY OF LIKE, JUXTAPOSED GUIDE ELEMENTS, EACH GUIDE ELEMENT HAVING A RELATIVELY THIN BEAKLIKE GUIDE PORTION INCLUDING AN UPPER AND A LOWER JAW, SAID JAWS HAVING CONVERGING ENDS AND BEING ADAPTED TO RECEIVE THE WEFT THREAD INSERTING DEVICE THEREBETWEEN AND ENTERING AND LEAVING THE SHED BETWEEN WARP THREADS DURING EACH MOVEMENT OF THE GUIDE, EACH OF SAID GUIDE ELEMENTS HAVING A RELATIVELY THICK FOOT PORTION WHICH IS ADJACENT TO THE FOOT PORTIONS OF THE JUXTAPOSED GUIDE ELEMENTS, THE LOWER JAW FORMING A RUNNING SURFACE CONFORMING SUBSTANTIALLY TO THE CROSS-SECTIONAL CONFIGURATION OF THE LOWER PART OF THE WEFT THREAD INSERTING DEVICE RUNNING ON SAID RUNNING SURFACE, SAID UPPER JAW OF EACH GUIDE ELEMENT BEING THICKER THAN SAID LOWER JAW FOR PARTING THE WARP THREADS WHEN SAID GUIDE PORTION ENTERS AND LEAVES THE SHED. 